import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

/**
 * \* Created with IntelliJ IDEA.
 * \* User: Administrator
 * \* Date: 2021/11/29
 * \* Time: 18:40
 * \* To change this template use File | Settings | File Templates.
 * \* Description:
 * \
 */


public class TestDemo {

    public static void main(String[] args) {
        ArrayList<String> list=new ArrayList<>();
        Scanner scanner=new Scanner(System.in);
        String str1=scanner.nextLine();
        String str2=scanner.nextLine();
        for(int i=0;i<str1.length();i++){
            char ch=str1.charAt(i);
            if(!str2.contains(ch+"")){
                System.out.println(list.add(ch + ""));
            }
        }
    }
    public static void main3(String[] args) {
        ArrayList<String> list1=new ArrayList<>();
        //第一次add的时候，才会分配大小10
        //扩容1.5倍进行
        List<String> list3=new ArrayList<>();
        //区别：此时list1方法没有list3多

        list1.add("abg");
        System.out.println(list1);
        ArrayList<String> list2=new ArrayList<>(34);

    }

    public static String func(String str){
        StringBuffer sb=new StringBuffer();
        for(int i=0;i<str.length();i++){
            char ch=str.charAt(i);
            if(!sb.toString().contains(ch+"")){
                sb.append(ch);
            }
        }
        return sb.toString();
    }
    public static String func1(String str){
        StringBuffer sb=new StringBuffer();
        int[] arr=new int[127];
        for(int i=0;i<str.length();i++){
            char ch=str.charAt(i);
            if(arr[ch]==0){
                sb.append(ch);
                arr[ch]=1;
            }
        }
        return sb.toString();
    }

    public static void main1(String[] args) {
        Scanner scanner=new Scanner(System.in);
        String str=scanner.nextLine();
        String ret=func(str);
        System.out.println(ret);
    }
}
